williams



Jan. 20, 1959 D. L.. WILLIAMS R- 24,592

APPARATUS Foa SERVING A STRAND on A TRAVELLING com 2 Sheets-Sheet 1Original Filed May 12', 1954 Jan-.20) 1959 n. WILLIAMS v Re.` 24,592APPARATUS Foa SERVING A STRAND on A TRAVELLING com1 original 'Filed my12,A 1954 2 sheets-sen UnitedStates Patent O APPARATUS FOR SERVING ASTRAND ON A TRAVELLING CORE Dean L. Williams, Rome, N. Y., assigner toRome Cable Corporation, Rome, N. Y., a corporation of New York OriginalNo. 2,807,129, dated September 24, 1957, Serial No. 429,299, May 12,1954. Application for reissue February 24, 1958, 'Serial No. 717,284

19 Claims. (Cl. 57-18) Matter enclosed in heavy brackets appears in theoriginal patent but forms no part of this reissue specification; matterprinted in italics indicates the additions made by reissue.

This invention relates to apparatus for serving a strand onto and arounda travelling core. The word strand is used broadly and includes tapes,yarn, thread and the like, of paper, glass fiber, cotton or othercovering or insulating material. The word core is used broadly andincludes thread, yarn, cord, rope including metal rope, wire, cable andthe like.

The invention is described herein in connection with winding a coveringof insulating tape around a travelling wire or cable. Devices for thispurpose customarily have comprised a unitary hollow shaft havingdisposed concentrically around its front end a flyer, which isessentially a cup-like member opening forwardly and carrying one or morestrand guide pins. is pulled through the hollow shaft as the flyer isrotated at high speed. The strand is supplied in a package called a copwhich is furnished wound on a tube usually made of cardboard. The tubewith the cop wound thereon is placed on a sleeve which is rotatable onthe hollow shaft within said cup-like member or flyer. As the flyerrotates the strand is unwound from the cop and guided rst outwardly tothe periphery of the yer and then inwardly to and around the core. Thespeed of winding of the strand relative to the axial speed of travel ofthe' core determines whether the core is lap wound, butt wound or spacewound. The sleeve is mounted so that it can rotate with respect to thehollow shaft and said cup-like member as the strand is unwound from thecop, and the rotation of the sleeve is retarded by brake means to causethe strand to be wound on the core under slight tension.

It is desirable to run a flyer as fast as possible consistent with ahigh quality product, which is one comprising a strand served evenlyaround a core, under uniform tension. Flyers heretofore available aredecient in many respects. When used at high speed they are subject tovibration and erratic action of the brake means, which affects therotation of the cop. These defects in turn cause breakage of the strandand skips in the core covering.

The brake means of the prior art could not be adjusted without stoppingthe whole serving apparatus including means for advancing the wire orcable.

The sleeve on which the cop carrying tube is mounted rnust be rotatablewith respect to the hollow shaft and surrounding cup-like flyer but thetubular members on which the standard packages or cops of servingmaterial are supplied are of small diameter, ordinarily having an insidediameter of l/s" or 21/8" and there is not room between the hollow shaftand the sleeve for even the smallest prelubricated and sealed ballbearing assemblies which are commercially available, comprisinginner andouter races separated by ball bearings. It has heretofore been customaryto rotatably support the sleeve within this space using cone type ballbearings. It has been believed that this arrangement was necessaryalthough` The core to be coveredv dirt out.

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it has been recognized that it has several disadvantages which havecaused such bearing means to become obsolete for most applications. Inprior art devices of this kind it has been difficult toseal in lubricantand keep It has also been ditlicult to reduce the radial play of thesleeve to a negligible amount. Furthermore use of the cone land ballarrangement entails having portions of the surfaces of said hollow shaftand of said sleeve especially hardened to serve as bearing surfaces, inorder to avoid undue wear. This involves special custom work which isvery expensive compared to the cost of the sealed ball bearingassemblies which are commercially available. These are relativelyinexpensive since they are manufactured in large volume.

Furthermore, in apparatus now used for serving a strand around and ontoa wire or cable core the cops are held on the rotating sleeve byfriction, between the tube on which the cop is wound, and the sleeve,and the frictional grip is not adjustable. This requires very greataccuracy in manufacturing the tubular members, the tolerance permittedbeing only on the order of .O05 of an inch. This requirement renders thecost of the tubular members very high.

It is an object of the invention to provide serving apparatus which hasa minimum of loose parts and is characterized by absence of vibration.

Another object of the invention is to provide serving apparatus in whicha sleeve adapted to receive cops of serving material wound on-tubes ofstandard diameter may be supported for rotation on prelubricated sealedball bearing assembly units of a size nowcommercially available, anddisposed in such a way that the cop mounting sleeve is substantiallyfree of radial or axial play, thus eliminating one of the principalcauses of vibration in prior art devices.

Another object of the invention is to provide serving apparatus withbrake means which is simple in action and which can be adjusted whilethe flyer is in motion.

Another object of this invention is to provide the copmounting sleevewith means for varying its diameter thus providing dependable frictionalengagement between the sleeve and tubular members on which the copI iswound while permitting substantial tolerance in the diameter of saidtubes.

Other objects of the invention will be in part obvious or in partpointed out hereinafter.

The invention accordingly consists in the features of construction,combinations of elements, arrangements of parts, and in the severalsteps and relation and order of each of said steps to one or more of theYothers thereof, all as willbe pointed out in the following description,and the scope of the application of which will be indicated in thefollowing claims` The invention will best be understood if the followingdescription is read in connection with the drawings, in which- Figure lis a side elevation partly in section of an embodiment of the invention;

Figure 2 isa front elevation of the apparatus shown in Figure l;r e

. Figure 3 is a vertical section taken on the line A3- of Figure l; and

Figure 4 is a fragmental sectional View taken on the the line 4 4 ofFigure 3.

Prior art apparatus for applying a strand to a traveling core hasusually consisted of-a long unitary hollow shaft mounted in two pillowblocks, or a similar bearing arrangement, and theV entire shaft has beenrotated. In

contrast the improved apparatus disclosed herein corn- Aprisesv atwo-part hollow shaft, the rst or rear part 10 being stationary andsupported from its rear end, and

the second or front part 22 being integral, or otherwise combined, witha flyer 20 and rotatable with the yer,`

and the combined shaft 22 and yer 20 being supported from the rear endand rotated by driving means rotatable around said rear shaft 10.

The driving means shown is the sleeve 14 mounted for rotation aroundsaid stationary shaft member 10, on ball bearing assembly units 12,which are preferably of the prelubricated sealed type which are nowcommercially available. Sleeve 14 has adjacent its rear end a drivepulley 16, adapted to be driven by a V-belt drive, and having adjacentits front end the circular mounting ange 18 which is provided with anumber of holes h, spaced at equal intervals and extending through theflange axially of shaft member 10.

Positioned in front of stationary hollow shaft and aligned with it isthe hollow shaft 22. Shaft 22 is interconnected with the yer 20, whichis cup-shaped and has a front portion 20a and a rear portion 20c of lessdiameter than the front portion, interconnected by a radially extendingportion 20b, by the circular radial web 21 extending between the rearend of shaft 22 and the rear portion 20c of the flyer. The rear portion20c of the flyer comprises a rearwardly extending circular flange 25which abu-ts against the circular mounting flange 18 of drive member 14and has the internally threaded bores b in is rear end face to receivescrews bl inserted through the holes h in said mounting flange 18 tointerconnect flanges 18 and 25 for supporting the combination of shaft22 and flyer 20 and to rotate them when drive member 14 is rotated.

Surrounding front shaft 22, between it and the portion 20a of ilyer 20,is the cop 'mounting sleeve 26. It will be noted that sleeve 26 isspaced radially from shaft 22, and that it is supported adjacent itsrear end Aon ball bearing assemblies 28, which are preferably of theprelubricated and sealed unit type now commercially available,positioned between the rear end of said [shaft 22] sleeve 26 and thesurrounding rear portion 20c of flyer 20, which is of less diameter thanits forward portion 20a.

The cop receiving portion of said sleeve 2-6 extends from its front endto the shoulder 30. The diameter of this portion of sleeve 26 issubstantially the same as the inside diameter of tubes 32 on which thecops of tape are wound and which, as stated above, are at the presentl ltime furnished in sizes of 1%" and 21/8" inside diameter.

As shown in Figure l this front portion of sleeve 26 is reduced indiameter to the shoulder 34 and filling the space thus provided aroundsleeve 26 are the rings 36, 38, 39 and 40, axially movable on saidshaft. Rings 38 and 40 respectively are expansion rings which may be ofcompressed axially they expand radially and are thus able to provide afriction grip for cop carrying tubular members 32 which would otherwiset loosely around said sleeve 26.

Extending into sleeve 26 from its front end is a bore 41 in which anAllan cap screw 42 is insertable through a bore 43 in the radiallyextending flange portion 44a of the cop locking sleeve 44 which extendsfrom the front into the space between shaft member 22 and sleeve 26, andis keyed to sleeve 26 by key 45 for rotation therewith around shaft 32.It will be seen that by tightening the screw 42 the flange 44a of saidcop locking sleeve 44 is caused to exert pressure acting axially on saidrings 36, 38, 39 and 40, thus causing the said expansion rings 38 and 40to expand radially. Upon loosening screw 42 the pressure acting axiallyon said rings is relieved and the radial expansion of rings 38 and 40 iscorrespondingly decreased. This means of adjusting the effectivediameter of sleeve 26 is of considerable practical importance because itgreatly increases the diameter tolerance permitted in the manufacture ofthe tubes 32, on which cops of strand material are wound, thusmaterially decreasing the cost of such tubes.

The rear portion of sleeve 26, to the rear of shoulder 30 and radialange 46 [48], comprises portions of relation to the rear of frontbearing assembly 28, a.

known kind and are characterized in that, as they are differentdiameter. The resulting stepped formation provides a shoulder s1 inabutting relation to the front of front bearing assembly 28 and ashoulder s4 in abutting relation to the front of rear bearing assembly28.

The portion 20c of the flyer comprises stepped portions of differentdiameter providing a shoulder s2 in abutting shoulder s3 in abuttingrelation to the front of rear bearing assembly 28, and a shoulder S5 inabutting relation to the rear of rear bearing assembly 28. In additionthe rear bearing 28 is held from moving rearwardly on shaft 22 by thenut 27 screwed around its rear extremity and spaced from the bearing bythe washer 29.

The annular space available between the rear ends of flyer portion 251eand the rear portion of sleeve 26 is much greater than the space betweenshaft 22 and the forward portion of sleeve 26, which receives the tubes32 on which the cops are wound, and the diameter of which is limited bythe size of the diameter of tubes now commerically available. As aresult ball bearing assemblies of the sealed self lubricated type whichare mass produced and commercially available may be employed thusovercoming one of the deficiencies of prior art apparatus of the kinddescribed. Furthermore the stepped opposing surfaces of the flyer andsleeve provide shoulders which prevent relative movement between thebearings 28 and said llyer and sleeve 26, and since the flyer and[sleeve 26] shaft 22 are interconnected or integral this structure alsoserves to prevent vibratory movement of sleeve 26 axially o-f shaft 22.

Similarly shaft 10' is stepped to provide a shoulder S5 abutting therearface of front bearing assembly 12 and the shoulder S7 abuttingagainst the rear face of the rear bearing 12, and driving member 14 isstepped thereby providing a shoulder s3 abutting the rear face of frontbearing assembly 12 and the shoulder s abutting the front face of rearbearing assembly 12. In addition, front bearing assembly 12 is heldagainst movement forwardly on shaft 10 by the nut 90 screwed around theforward end of shaft 10 and the washer 91 interposed between said nutand said front bearing 12.

Projecting radially from sleeve 26 to the Irear of said shoulder 30 is acircular flange 46 [48] and demountably mounted on said flange as byscrews 48 [49] is a disk 50 which may for example be made of anysuitable material, such for example as metal or plastic, against whichbear the friction pads 52, which may for example be of cork, and arecontained within cup-shaped holders 54 mounted on spring steel arms 56which are respectively supported on spacing members 58projectingforwardly from the radially extending portion 20h of flyer 20.The said supporting spring steel members 56 have the extentions 57extending belowthe friction pads 52 into abutting relation with theinner ends of control rods 60 respectively, which are disposed inparallel relation to shafts 10 and 22 and are movable axially of saidshafts to increase or decrease the pressure with which said frictionpads 52 contact the said friction disk 50 by moving the free ends ofsaid spring extensions 57 of said spring arms 56 toward or away fromsaid friction disk.

Movement of said control rods 60 toward or away from said spring members57 is controlled by rotation of the knurled annular ring 62 the innersurface of which is threadedly engaged with the annular adjusting screw64 which extends around stationary shaft 10 and supports bearingassembly 66. Adjusting screw 64 moves axially on stationary shaft 10,and is prevented from turning by key 65, placed in a slot in shaft 10.Key 65 is disposed 4axially between shoulder s1 on shaft 10, and therear face of the rear bearing assent-bly 12.

lRing 62 is held from moving axially of shat'l by the split ring `68which is secured to the laterally extending ange portion l63 of ring 62by screw 70 and extends into, and travels in, a groove 72 in theperiphery of a stationary ring 74 surrounding the rear extremity ofshaft and secured by screws 76 to support member 78. Between knurledadjusting ring 62 and stationary ring 74 is the friction spring member75 which `serves to maintain friction between members 62 and 74 toprevent inadvertent relative movement between them.

Around `bearing assembly f66 the ring 80 is provided, having in itsfront face the 'bores 82 in which the rear ends of said control rods 60are received. The rear ends of said rods `are held `in position withinsaid bores 82 Iby the locking screws 84 respectively which extend fromthe periphery of ring 80 -into said bores. As the knurled ring 62 isturned the `adjusting screw 64, bearing assembly 66, and the ring member'80, are moved back and forth :axially of said shaft 10 as desiredcausing the front ends of said control rods 60, which ,are in continuouscontact with said brake pad spring retaining members 57 to position saidmembers to increase or decrease the braking force of the friction pads52 on said friction disk 50 thereby adjusting the drag between sleeve 26and riiyer to control the tension yon the strand being unwound from thecop Iand served on the core which is travelling successively throughvsaid hollow `shafts 1.0 and 22.

In its travel through said shafts 10 and 22 Ithe travelling core isguided and maintained out of contact with the ro- 'rating shaft member22 by an inwardly extending flange 92 at the front end of stationaryshaft 10 and by the ring 94 positioned within shaft 22 iat its yfrontend :and held in place by screw 96 extending throughvthe shaft and thenose piece 98, provided at the front end of said rotating hollow shaft22. Projecting forwardly fromnose piece 98 and integral with it is theear 100. Pivotally mounted on ear 100 by pivot yscrew 102 the bracket104 from `which extends guide pin 106. The guide pin 106 is an angularlybent member the lower free portion 106a of which is susbtantiallyparallel lto the core travelling through said sleeves 10 and 22 but maybe .swung around its pivot toward or away from said core to control theangle at which .a `strand passing over it is served to and around thetravelling core.

As the strand `t is unwrapped from 'the cop it 'first passes around aguide pin 110 supported on the inner surace 0f the ilyer between the twospaced brackets 112 and 114 held to the inner surface of the flyer bythe screws 116 extending through the wall of the flyer. After passingaround pin 110 the strand is 'advanced to and around vthe guide post118, projecting radially inward from the inner surface of the flyer, to'and around the bent over extremity 120a of the inwardly extending guide120. From the guide member 120 the strand passes to and around the bentover outer portion 106e. of guide pin 106, the angular position of whichVdetermines the angle at which the strand is served upon |the travellingcore c.

It will be noted that the guide pin 110 extends substantially at rightangles to the guide post 118, which in 'turn is substantially at rightyangles to the bent over end portion 120a of guide 120, and the bentover end portion 120a is substantially at right angles to the bent overend portion 106a of guide pin 106. Thus the strand, in travelling fromythe cop Lto the core, passes over four guide members and in eachinstance its path of ltravel to and from each guide member issubstantially .at fright angles to the guide member, and its path oftravel to a guide member is substantially -at right angles to its pathof travel from the guide member to the next guide member. Thisdisposition of the guide means results in a relatively uniform tensionthroughout the cross section of the strand as it is paid off from `thecop and served onto the travelling core. The device described herein hasthe` advantages that it makes possible high speed of .strand applicationwithout vibration which causes lbreakage and excess wear; longer weardue to improved bearing means, and more unifrm application of the strandto the travelling core with less skips due to `the freedom of the devicefrom vibration. it has the further advantages that it requires lessspace than the prior art yers; cops .may be installed and removed withgreater ease; `and the cop carrying tubes can be supplied at less costsince their diameter measurement becomes less critica-l. The suspensionof 'the device from the rear 4end together with the provision of ,atwo-part shaft including .a rotatable Vfront shaft and a flyer andsleeve the rear portions of which [is] are stepped makes possible theuse of Vprelubricated sealed bearing units eliminating the problem ofcleaning and lubricating las 4well as giving 'the flyer ylonger life;and, due to the construction of the hollow shaft in two partsinterconnected through the mounting ange 18 removal :of the rearbearings, if required, can be accomplished in a simple manner bydetaching the front sha-ft and flyer from the drive sleeve whichisrotatable around rear shaft l10.` A

It should he understood that the present disclosure is for the purposeof .illustration only and that lthis inven- -ltion includes allmodifications and equivalents which fall 'ing said second shaft andflyer with said rotatable means for rotation with said rotatable means,a `sleeve surrounding said second sha-it, and rneans disposed betweensaid sleeve and Vsaid ilyer for spacing said sleeve from said secondshaft and mounting said slee-ve for rotation around said second shaft.

2. The apparatus claimed in claim l :in which said rotatable meanscomprises a radial iiange, yand the connec- Ition means of said secondShaft 'and ilyer comprises a ilange portion extending rearwardly towardsaid radial flange, and means are provided for interconnecting saidradial flange and said ilange portion.

3. The apparatus lclaimed in claim l in which said sleeve comprises afront lcop receiving portion and a rear portion, the rear portions ofsaid flyer and said sleeve, respectively comprising portions ofdifferent diameter, the said portions of the sleeve and yer jbeingopposed with a portion of one opposed by a portion of lt'he other whichis oppositely modied in diameter, and `sealed self lubricating ballbearing assembly means is provided between the said rear portions ofsaid iiyer' and sleeve.

4, The apparatus claimed in claim 3 in which .a rear portion of `saidsecond hollow .shaft is spaced radially from a rear portion of the flyerby la distance greater than the radial distance between a forwardportion of said second shaft and the inner surface of a portion of saidsleeve surrounding the said forward portion of said second shaft.

5. The apparatus `claimed in claim l i-n which rear portions of saidcup-shaped yer and said sleeve respectively have a plurality of pairs of,opposed portions of different diameter forming shoulders, and sealedself lubricating ball bearing assembly means `is provided between thesaid opposed portions of said flyer and sleeve, said shoulders coactingwith said ball bearing assembly means respestively to prevent relativemovement between said sleeve and said second shaft axially ofsaidrshaft.

6. The apparatus claimed in claim 1 in which said sleeve is mounted onball bearing assembly means nterposed between it and the inner surfaceof said flyer,

and shoulder means is provided on said sleeve positioned to coact withsaid ball bearing assembly means to prevent relative movement axially ofsaid second shaft, between said sleeve and the combination comprisingsaid second shaft and iiyer [axially of said second shaftl.

7. The apparatus claimed in claim 1 in which the rotatable mountingmeans for said sleeve comprises ball bearing assembly means and in whichsaid second shaft has a radially extending flange positioned to coactwith said ball bearing assembly means to prevent axial relative movementbetween said sleeve and the combination comprising said second shaft andyer.

8. The apparatus claimed in claim 1 in which said cup-shaped flyer isconnected to said second shaft by a radially extending web projectingfrom said second shaft adjacent its rear end, and said sleeve isdisposed concentrically around said second hollow shaft but spacedradially from said shaft and is supported on bearing means positionedbetween said flyer and the rear end portion of said sleeve.

9. The apparatus claimed in claim 1 in which said cup-shaped flyer isconnected to said second shaft by a radially extending web projectingfrom said second shaft adjacent its rear end, and said sleeve isdisposed concentrically around said second hollow shaft but spacedradially from said shaft and is supported on bearing means positionedbetween said flyer and the rear end portion of said sleeve, the rear endportion of said sleeve comprising portions of differentdiameteruproviding radial shoulder means which coact with said bearingmeans for preventing movement of said sleeve axially of said secondshaft.

10. The apparatus claimed in claim l in which said cup-shaped flyer isconnected to said second shaft by a radially extending web projectingfrom said second shaft adjacent its rear end, and said sleeve isdisposed concentrically around said second hollow shaft but spacedradially from said shaft and is supported on bearing means positionedbetween said yer and the rear end portion of said sleeve, the rear endportion of said flyer comprising portions of different diameterproviding radial shoulder means which coact with said bearing means forpreventing movement of said sleeve axially of said second shaft.

11. The apparatus claimed in claim 1 in which said flyer comprises aforward portion and a rear portion, the rear portion being of lessdiameter than the forward portion and itself comprising portions ofdifferent inside diameter, the rear end portion of said sleevesurrounded by said rear portion of said flyer comprising v portions ofdifferent diameter radially aligned respectively with the said portionsof the rear portion vof said flyer to provide a plurality of annularseats between said flyer and sleeve, disposed at different distancesradially from said second shaft, to respectively receive ball bearingassemblies and provide shoulder means in abutting relation to said ballbearing assemblies respectively to prevent movement of said sleeveaxially of said second shaft.

12. Apparatus for winding a strand on a moving core comprising a firsthollow shaft, a composite flyer and a second hollow shaft, said secondhollow shaft being axially aligned with, but separate from said firstshaft, rotatable means mounted for rotation around said first shaft,means interconnecting said rotatable means with said composite flyer andsecond shaft, a sleeve mounted for rotation around said second shaft andhaving a forward portion for receiving a cop of strand material to beserved onto a core travelling through said shafts successively, and arear portion, and bearing means disposed between said flyer and the saidrear portion of said sleeve for supporting said sleeve.

13. Apparatus for winding a strand on a moving core comprising a firsthollow shaft, a composite flyer and second hollow shaft, said secondhollow shaft being axially aligned with, but separate from said firstshaft, rotatable means mounted for rotation around said first shaft,means interconnecting said rotatable means with said composite flyer andsecond shaft, a sleeve mounted for rotation around said second shaft andhaving a portion for receiving a cop of strand material to be servedonto a core travelling through said shaft successively, brake means forsaid sleeve and means for manually adjusting said brake means withoutstopping the winding operation to control the braking force applied tosaid sleeve.

14. vApparatus for winding a strand on a moving core comprising la firsthollow shaft, a composite flyer and second hollow shaft, said secondhollow shaft being axiallyaligned with, but separate from said firstshaft, rotatable means mounted for rotation around said first shaft,means interconnecting said rotatable means with said composite flyer andsecond shaft, a sleeve mounted for rotation around said second shaft andhaving a portion for receiving a cop of strand material to be servedonto .a core travelling vthrough said shafts successively, and brakemeans for said sleeve comprising friction pads supported from the flyerby spring members and movable toward or away from friction meanssupported on said sleeve, in which means are provided, operable at alltimes including when said flyer is rotating to control the portion ofsaid spring member to thereby adjust the braking force between said padsand said friction means supported on the sleeve.

15. The apparatus claimed in claim 14 in which bores areprovidedextending through said composite flyer and second shaft and through themeans for rotating said composite'flyer and second shaft, and brakecontrol rod meansis inserted in said bores respectively into contactwith the spring member supporting said pads respectively, and means areprovided remote from said.

brake means for moving said control rod means to adjust the position ofthe said spring member toward or away from the friction means carried bysaid sleeve.

16. The apparatus claimed in claim 1 in which a number of guide meansare mounted on said composite flyer and second shaft for guiding astrand in its t'ravel between said cop and said moving core around whichit is served, the guiding surface of each of said guide means beingdisposed at right angles to the guide surface of the preceding andfollowing guide means and controlling the strand so that upon leavingeach guide surface it travels substantially at right angles to its lineof travel to the guide surface.

17. The apparatus claimed in claim 12 including a nose piece comprisinga ring fixed lto the outer end of said second shaft and having an earprojecting forwardly axially of the shaft and a strandl guide swingablysupported from said ear to adjust the angular position of said guidesurface relative'to the core to control the angle at which a strandpassing over said guide surface is served onto the travelling core.

18. The apparatus claimed in claim 1 in which said spacing and mountingmeans comprise ball bearings disposed between the rear end of saidsleeve and theV flyer.

19. The apparatus claimed in claim 14 in which the means for adjustingthe said braking force comprises control rod means, slidably mounted forrotation with said flyer and said second shaft and movable by remotecontrol means to adjust the frictional contact between said pads andsaid-friction means.

References Cited in the file of this patent or the original patentUNITED STATES PATENTS 353,938 Harrison Dec. 7, 1886 1,890,929 BorgesonDec. 13, 1932 1,934,363 Littlefield Nov. 7, 1933 2,066,659 Templeton etal. Jan. 5, 1937 2,666,289 Bunch Jan. 19, 1954 FOREIGN PATENTS 128,708 lSwitzerland Dec. 1, 1928

